1. Technical Field
This invention relates to surgical apparatus and procedures in general, and more particularly to surgical apparatus and procedures for reconstructing a ligament.
2. Background of Related Art
A ligament is a piece of fibrous tissue which connects one bone to another. Ligaments are frequently damaged (e.g., detached or torn or ruptured, etc.) as the result of injury and/or accident. A damaged ligament can cause instability, impede proper motion of a joint and cause pain. Various procedures have been developed to repair or replace a damaged ligament. The specific procedure used depends on the particular ligament which is to be restored and on the extent of the damage.
One ligament which is frequently damaged as the result of injury and/or accident is the anterior cruciate ligament (i.e., the ACL). Looking first at FIGS. 1 and 2, it will be seen that the ACL 5 extends between the top of the tibia 10 and the bottom of the femur 15. A damaged ACL can cause instability of the knee joint and cause substantial pain and arthritis. For this reason, ACL reconstruction is a common procedure with more than 100,000 cases being performed in the United States annually.
Various procedures have been developed to restore and/or reconstruct a damaged ACL through a graft ligament replacement. Traditionally, this procedure is performed utilizing a trans-tibial approach. In this approach, a tibial tunnel or bone tunnel 20 is created in tibia 20 by drilling up through tibia 10. Bone tunnel 20 is then used to access an inner surface of femur 15 to drill a bone tunnel 25 up into femur 15. More particularly, once tibial tunnel 20 is created, a conventional femoral guide, often referred to as an “over-the-top” guide (FIG. 4), is used to accurately locate the femoral tunnel 25. More specifically, the “over-the-top” guide is placed through the tibial tunnel, across the joint, through the femoral notch, and then into position so that the distal finger of the guide is positioned against the backside of the femur. (FIG. 5). Proper placement of the femoral tunnel is imperative in order for the ACL graft to be properly positioned on the femur. However, as a result of using the aforementioned trans-tibial technique and the aforementioned conventional “over-the-top” femoral guide, the position of the femoral tunnel is effectively dictated by the position of the first-drilled tibial tunnel. This often results in a femoral tunnel position, and thus, an ACL reconstruction (i.e., graft orientation, etc.) that is less than optimal.
In an attempt to better position the femoral tunnel, surgeons have recently begun utilizing the so-called “medial portal technique” to drill and create the femoral tunnel. By drilling the femoral tunnel through the medial portal or an accessory portal, the femoral and tibial tunnels may be drilled independently of one another and, therefore, in a more appropriate anatomical position.
As shown in FIG. 6, when drilling the femoral tunnel through the medial portal, surgeons typically still use the same “over-the-top” femoral guide used during the aforementioned trans-tibial approach. However, because the “over-the-top” femoral guide is designed for use in a trans-tibial approach, the “over-the-top” femoral guide is not ideal for use in a medial portal approach. These “over-the-top” femoral guides generally have narrow-shaped distal tip geometries to aid in their ability to pass through the tibial tunnel. In addition, such femoral guides have an offset spatula design to hook the posterior femoral notch, thereby aiding in positioning of the guide. Aside from this spatula design, these femoral guides have no other specific referencing geometries for properly positioning the femoral tunnel.
Traditionally, surgeons utilize what is known as a “clock face” orientation in order to decide where to place the femoral tunnel within the notch of knee. This clock face orientation technique designates positions along the notch from 9 o'clock to 3 o'clock, depending on which knee is being reconstructed. This technique, while seemingly simplistic, is limited by a number of factors, one being that the positioning of the imaginary clock face along the notch is completely subjective and hence widely affected by the specific implementation of the surgeon. Therefore, it would be beneficial to have a femoral guide for use in medial approach ACL reconstruction surgery that is configured for more accurate femoral tunnel positioning. In addition, it would be beneficial if the femoral guide is designed in such a way that it might also be utilized during a trans-tibial approach.